Index: trunk/src_plugins/lib_compat_help/pstk_help.c
===================================================================
--- trunk/src_plugins/lib_compat_help/pstk_help.c	(revision 27781)
+++ trunk/src_plugins/lib_compat_help/pstk_help.c	(revision 27782)
@@ -326,6 +326,24 @@
 	dst->x[3] = -width; dst->y[3] = +height;
 }
 
+void pcb_shape_rect_trdelta(pcb_pstk_shape_t *shape, pcb_coord_t width, pcb_coord_t height, pcb_coord_t dx, pcb_coord_t dy)
+{
+	pcb_pstk_poly_t *dst = &shape->data.poly;
+
+	pcb_pstk_shape_alloc_poly(dst, 4);
+	shape->shape = PCB_PSSH_POLY;
+
+	width/=2;
+	height/=2;
+	dx/=2;
+	dy/=2;
+
+	dst->x[0] = -width+dx; dst->y[0] = -height-dy;
+	dst->x[1] = +width-dx; dst->y[1] = -height+dy;
+	dst->x[2] = +width+dx; dst->y[2] = +height-dy;
+	dst->x[3] = -width-dx; dst->y[3] = +height+dy;
+}
+
 void pcb_shape_oval(pcb_pstk_shape_t *shape, pcb_coord_t width, pcb_coord_t height)
 {
 	shape->shape = PCB_PSSH_LINE;
Index: trunk/src_plugins/lib_compat_help/pstk_help.h
===================================================================
--- trunk/src_plugins/lib_compat_help/pstk_help.h	(revision 27781)
+++ trunk/src_plugins/lib_compat_help/pstk_help.h	(revision 27782)
@@ -26,5 +26,10 @@
 void pcb_shape_rect(pcb_pstk_shape_t *shape, pcb_coord_t width, pcb_coord_t height);
 void pcb_shape_oval(pcb_pstk_shape_t *shape, pcb_coord_t width, pcb_coord_t height);
 
+/* trapezoid: deform the rectangle so that upper horizontal edge is smaller
+   by dx and lower horizontal edge is larger by dx; same happens to the vertical
+   edges and dy. */
+void pcb_shape_rect_trdelta(pcb_pstk_shape_t *shape, pcb_coord_t width, pcb_coord_t height, pcb_coord_t dx, pcb_coord_t dy);
 
+
 #endif